<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>倒序输出</title>
	<script type="text/javascript">
		var num1=Number(prompt('请输入一个三位数：'));
		if (num1<100||num1>=1000||parseInt(num1)!==num1) {
			console.log('请输入一个三位数！');
		}
		else{
			num2=num1%100;
			num3=num2%10;
			num1=(num1-num2)/100;
			num2=(num2-num3)/10;
			var num=num3*100+num2*10+num1;
			console.log(num);
		}
	
	</script>
</head>
<body>
	
</body>
</html>